Backspacing apparatus for dictating machines



Jilly. 27, 1965 TAYLOR 3,197,213

BACKSPACING APPARATUS FOR DICTATING MACHINES Filed March 29, 1963 3 Sheets-Sheet l I2 q "2 3,-? O 56 26 i J T 3 2 M 30 38 INVENTOR July 27, 1965 A. TAYLOR 3,197,213

BACKSPACING APPARATUS FOR DICTATING MACHINES Filed March 29, 1963 s Sheets-Sheet 2' INVENTOR uZbrg/eam Taylor m ms w July 27, 1965 TAYLOR 3,197,213 BACKSPACING APPARATUS FOR DICTATING MACHINES Filed March 29, 1963 3 Sheets-Sheet 3 INVENTOR Argzjzam Tailor @g, mf lqrvw United States Patent 3,1?1213 BACKPACHNG APPARATUS FUR BHQTAT'N'G MAUHENES This invention relates to dictation apparatus of the type having a carriage for eilecting relative movement between a translating head and a rotatable sound record. More in particular, this invention relates to improved means for back-spacing the carriage of such dictation apparatus.

The invention is described herein as embodied in a transcribing machine, Le. a machine which is used by a secretary to reproduce previously recorded material for the purpose of typing the material in letter form, etc. However, it will be evident that the invention also is applicable to dictating machines including facilities for recording spoken messages.

The appartus to be described in detail hereinbelow is of the type wherein advancing movement of the machine carriage is effected by the usual rotating feed screw which engages a feed nut mounted on the carriage. Also mounted on the carriage is electromagnetic means which is controllable remotely by the machine operator, and which serves to rotate the feed nut in incremental steps while the feed screw is stopped. By these means, the carriage is walked back along the stationary feed screw until the desired portion of the record is reached. Thereafter, the advancing movement of the carriage is resumed, by rotation of the feed screw, in order to play back the recorded material.

In the embodiment of the invention disclosed herein, the electromagnetic means for rotating the feed not comprises a first pole piece which is secured to the feed nut, and a second pole piece adapted to be shifted axially towards the first pole piece by magnetic attraction when both pole pieces are magnetized by an electrically energized coil. The shifting movement of the second pole iece is translated into a small angular movement of the first pole piece by positive-acting cam means arranged to effect a backspacing step of predetermined magnitude each time the coil is energized. When the coil is deenergized, a spring is operative to return the second pole piece to its normal position, without correspondingly rotating the first pole piece. Thus, through a ratchet-like action, the carriage may he stepped back precise increments by successive energizations of the magnetizing coil.

In accordance with a further aspect of this invention, a hollow magnetic cylinder is disposed between the two pole pieces referred to in the preceding paragraph. This hollow cylinder is arranged coaXially with respect to the pole pieces, and is formed with cam surfaces engageable by drive pins proiecting axially from the second pole piece. When the coil is energized, this cylinder is magnetically attracted to the first pole piece, and the two parts are thereby firmly locked together. The axial shifting movement of the second pole piece, resulting from energization of the coil, causes the pole piece drive pins to engage the cam surfaces in the hollow magnetic cylinder, and thereby rotate this cylinder which now is magnetically locked to the first pole piece. Since as mentioned hcreinabove the first pole piece is integrally connected to the feed nut, the cam action correspondingly rotates the feed nut about its axis on the carriage, and thus backspaces the carriage. Once the backspacing movement has been completed, continued energization of the coil holds the feed nut magnetically locked to the carriage, so that rotation of the feed screw will produce advancing movement of the carriage for transcribing operations.

To effect a complete backspacing cycle, the coil is first deenergized, thus releasing the hollow magnetic cylinder from its frictional gripping engagement with the first pole piece. Simultaneously, the second pole piece is shifted away from cam engagement with the hollow magnetic cylinder, and the latter is spring returned to its original rotational position about the axis of the two pole pieces, without, however, causing any corresponding return movement of the first pole piece. Thereafter, reenergization of the coil will reengage the magnetic cylinder and the first pole piece, and re-rotate the magnetic cylinder by cam action with the second pole piece so as to complete the backspacing cycle.

Accordingly, it is an object or" this invention to proide improved means for backspacing the carriage of a dictating machine. A further object of this invention is to provide structurally simple backspacing means which are reliable in operation yet inexpensive to manufacture. Other objects, aspects and advantages of this invention will in part he pointed out in, and in part apparent from, the following description considered together with the accompanying drawings in which:

FlGURE l is a bottom plan view of a portion of a transcribing machine incorporating the present invention;

FIGURE 2 is a cross-section taken along line 2-2 of FEGURE 1, showing the machine as it would appear in its upright position;

FIGURE 3 is a detail section taken along line 3-3 of FIGURE 1 to show the button-controlled switch;

FIGURE 4 is a cross-section taken along line i e of FIGURE 1, and showing the interior arrangement of the electromagnetic backspacing means;

FIGURE 5 is a detail action taken along line 5-5 of FIGURE 4, showing the drive pin and V-notch cam configuration; and

FIGURE 6 is an exploded perspective view of the electromagnetic backspacing means.

Referring now to 1, there is shown in bottom plan view a portion of a transcribing machine having a carriage till which is mounted on conventional guide rod means, such as indicated at 12, for travelling move ment with respect to a rotatable belt-type plastic sound record l-i supported on a mandrel 15. Further details of a transcribing machine or the general type shown herein are set forth in US. Patent 2,961,243, it being noted that FlGURES l and 2 herein correspond to FIG- URES 8 and 7 respectively of that patent.

This transcribing machine is provided with a conventional feed screw in parallel to guide rod 32 and adapted to be rotated at constant speed by the usual clutch-controlled motor. As shown in FIGURE 2, this feed screw is threadedly engaged with a normally non-rotating feed nut in the form of a wheel 33 secured to the carriage 1t).

As the feed screw rotates during a reproducing operation, the carriage is advanced at constant speed, in a forward direction, with respect to the record 114. Thus, the reproducing head 29, which is pivotally mounted on the carriage, is enabled to follow the previously-recorded helical grooves in the record 14 and thereby produce for the transcribing secretary sound signals corresponding to the recorded material.

Referring now also to FIGURES 4 and 6, it will be seen that the feed nut 18 is integral with a coaxial stub shaft 22 which is rotatably mounted in a bearing plate 24. This plate is fastened to the upper surface of carriage it) by machine screws 26, the latter serving also to secure to the lower carriage surface a cylindrical outer casing 23 for an electromagnetic rotating device generally indicated at 30. Device 30 includes upper and lower magnetic pole pieces 32 and 34 each comprising a horizontal discshaped part and an inwardly projecting central hub. The upper hub is formed with an axial bore within which is threadedly secured a reduced-diameter end of the feed nut shaft 22. Thus, it will be apparent that pole piece 32 is effectively integral with the feed nut.

The lower pole piece 34 serves as an armature for the device 34, and is supported for axial movement by means of a spring spider 36 fastened to the outer casing 28. This spider has three leaf spring arms 38 arranged in the form of a Y, each arm being screwed at its outer end to casing 23, and the common center portion being screwed to a central recess in pole piece 34. These spring arms are arranged to permit the desired amount of axial movement of the lower pole piece, e.g. about between the position shown in FIGURE 4 in solid outline and the position shown in broken outline, while preventing rotational movement of the pole piece relative to casing 28.

Disposed between the outer rims of the two pole pieces 32 and 34 is a hollow magnetic cylinder or ring 42 surrounding an electrically-energizable coil 44-. When this coil is deenergized, the lower pole piece is held by the spring spider 36 in the position shown in broken outline, cylinder 42 is held fairly close to the upper pole piece by small horizontal rods 46 which extend outwardly through cutouts in casing 28 and seat down against the casing. When coil 44 is energized, it produces magnetic flux through the magnetic parts of the solenoid, pulling the magnetic cylinder up against the upper pole piece to frictionally lock these two parts together, and simultaneously forcing the lower pole piece up towards the upper pole piece.

The outer rim of the lower pole piece 34 is provided with three upstanding drive pins 48 positioned at 120 intervals about the pole piece axis and projecting into corresponding V-shaped cam notches 541 formed in the lower edge of the hollow magnetic cylinder 42. When the coil 44 is deenergized, the lower pole piece and the cylinder are positioned with respect to each other in the manner indicated in broken outline in FIGURE 5, the cylinder being spring-urged (as will be described) to the left into engagement with the drive pins. When the coil is energized, the resulting upward movement of the lower pole piece forces the drive pins against the sloping side surfaces of the V-notches and thereby rotates the cylinder, as indicated by the arrow, to'the position shown in solid outline. In the preferred embodiment disclosed herein, the outer periphery of the cylinder was arranged to move about when the coil 44 was energized.

This rotary movement of the cylinder 42 produces a corresponding rotation of the upper pole piece 32, because the latter is magnetically clamped to the cylinder when coil 44 is energized. Rotation of the upper pole piece, in turn, causes a corresponding rotation of the feed nut 18, and thereby shifts the carriage lid backwards a predetermined small distance, e.g. sufiicient to move the reproducing head 2% back to the next preceding record groove.

The electromagnetic device 3a is maintained energized during normal transcribing operations, i.e. during reproduction of the record. With energizing current passing through coil 44, the feed nut is effectively locked to the carriage It and therefore it will be evident that rotation of feed screw 16 causes a corresponding advance of the carriage. 7

As seen in FIGURES 1 and 6, the magnetic cylinder 42 also is provided with a radial arm 52 carrying a pulley 54. Wrapped around this pulley is a string 56 one end of which is anchored to the carriage at 58, and the other end of which (see FIGURE 2) is directed around a carriage-mounted pulley 6ft to a horizontal pin 62 secured to the lever 64 which is pivoted at 65 and is operable to retract the reproducing head 2d by rotating this head about its axis 21. Connected between the carriage it and the pin 62 is a spring 66 tending to rotate lever 64 in a direction to retract the head from the record. While the electromagnetic device 30 is energized during transcribing operations, arm 52 is held in the position shown in solid outline in FIGURE 1, and the force applied to string 56 holds the lever 64 away from the reproducing head 20 so that the latter may engage the record under the usual spring bias force.

When the carriage is to be backspaced, the first step is to stop the feed screw 16 and deenergize the coil 44, for example by means of a conventional foot-operated control. This releases the hollow magnetic cylinder 42 from frictional engagement with the upper pole piece 32, and simultaneously the drive pins 48 are Withdrawn from cam notches 50 due to the return movement of the spring spider 36 to its neutral position.

Thus freed from the restraint of the drive pins 48, the cylinder 42 is rotated, to the position indicated in broken outline in FIGURE 5, by the force of the bias spring 65 which also retracts the reproducing head 20 from the record. Thereafter, to complete the backspacing cycle, coil 44 is reenergized, thus forcing the lower pole piece 34 upwards until it is stopped by the magnetic cylinder 42. This movement rotates cylinder 42 and the feed nut 18 one angular increment and correspondingly backspaces the carriage one step. During this backspacing step, the rotational movement of the cylinder 42 is transmitted by the string 56 to the retracting lever 64 for the reproducer head 26 and is effective to overcome the force of spring 66 so as to reengage the head with the record. Thus, as the backspacing step is completed, the stylus of the head settles down into a preceding record groove so that the material recorded in that groove can be played back again to the transcribing secretary.

A separate control is provided for conditioning the machine to permit a transcribed sound record to be replaced with a new record. For this purpose, there is provided a shaft in adapted to be rotated between Reproduce and Neutral positions from the front of the machine (eg by means of the usual geared buttons as in the above US. Patent 2,961,243). Mounted on this shaft is a small plastic cylinder 72. having an electrically-conductive coating 74. When the shaft 79 is in Reproduce position, this coating establishes electrical continuity between a pair of flexible switch arms '76 spring-urged against the plastic cylinder, and thereby completes the energizing circuit for coil 44. When the shaft is rotated to its Neutral position, this circuit is broken, coil 44 is deenergized, and reproduce head Ztl is retracted from the record by spring 66 as described hereinabove. In this condition, it may be noted, the feed nut 18 is free to rotate about its axis, so that the carriage can readily be shifted by hand, for example back to the starting point to begin transcription of the new record.

Although a preferred embodiment of the invention has been set forth in detail, it is desired to emphasize that this is not intended to be exhaustive or necessarily limitative; on the contrary, the showing herein is for the purpose of illustrating the invention and thus enable others skilled in the art to adapt the invention in such ways as meet the requirements of particular applications, it being understood that various modifications may be made without departing from the scope of the invention as limited by the prior art.

I claim:

1. Dictation apparatus comprising, in combination, a sound record supporting device, a record-cooperating translating device, a carriage for one of said devices mounted for travelling movement of said one device with respect to the other device, a rotatable feedscrew for driving said carriage in forward direction, a feed nut on said carriage engaged with said feed screw, means mounting said feed nut for rotary movement with respect to said carriage, locking means normally eifective to hold said feed nut stationary about its rotary axis so that the rotation of said feed screw produces advancing movement of the carriage, electromagnetic means on said carriage including an electrically-energizable coil, an armature shiftable in position by energization of said coil, and cam means responsive to movement of said armature and operable to rotate said feed nut about its rotational axis, thereby to shift said carriage in reverse direction relative to said feed screw.

2. For use with a sound reproducing machine having a carriage for effecting advancing movement between a .rotatable sound record and a transducing head cooperable with said record, and wherein said carriage includes a normally stationary feed nut engageable with a rotatable feed screw for producing the advancing movement thereof; backspacing apparatus comprising bearing means fior accommodating rotational movement of said feed nut, electromagnetic means including a remotely energizable coil mounted on said carriage, rotating means movable by said coil from an initial position to a second position so as to rotate said feed nut an incremental step when said coil is energized, locking means arranged to magnetically grip said feed nut when said coil is energized and to keep said feed nut stationary in the position to which it has been rotated, and means effective when said coil is deenergized to return said rotating means to its initial position without producing any rotary movement of said feed nut, whereby said carriage may be backspaced in successive increments by successive energizations of said coil.

3. For use with a sound reproducing machine having a carriage for effecting advancing movement between a rotatable sound record and a transducing head cooperable with said record, and wherein said carriage includes a normally stationary feed nut engageable with a rotatable feed screw for producing the advancing movement thereof; backspacing apparatus comprising bearing means for accommodating rotational movement of said feed nut with respect to said carriage, holding means normally operative to prevent rotation of said feed nut, a coil mounted on said carriage, a first pole piece integral with said feed nut, a second pole piece shiftable between first and second positions in response to energization of said coil, motion-translating means responsive to said shifting movement of said second pole piece and eiiective thereby to rotate said first pole piece and said feed nut about said bearing means so as to shift said carriage in reverse direction.

t. Apparatus as claimed in claim 3, including a magnetic member disposed between said two pole pieces and shiftable by magnetic attraction into gripping engagement with said first pole piece when said coil is energized, said motion-translating means including means on said magnetic member and engageable with corresponding means on said second pole piece.

5. Apparatus as claimed in claim 4-, wherein said magnetic member comprises a hollow magnetic cylinder surrounding said coil, said pole pieces including hub portions extending into the region in the interior of said coil.

6. Apparatus as claimed in claim 5, wherein said magnetic member has a notch in the edge thereof facing said second pole piece, and drive pin means on said second pole piece and engageable with said notch to cam said magnetic member rotationally when said second pole piece is moved axially.

7. Apparatus as claimed in claim 3, wherein said second pole piece is supported for axial movement by leaf spring means arranged to hold said second pole piece in the neutral spring position when said coil is deenergized.

8. Apparatus as claimed in claim '7, wherein said spring means is a spider the center of which is fastened to said second pole piece.

9. For use with a sound reproducing machine having a carriage for effecting advancing movement between a rotatable sound record and a transducing head cooperable with said record, and wherein said carriage includes a normally stationary feed nut engageable with a rotatable feed screw for producing the advancing movement thereof; backspacing apparatus comprising bearing means for accommodating rotational movement of said feed nut with respect to said carriage, holding means normally operative to prevent rotation of said feed nut, a coil mounted on said carriage, a magnetic pole piece shiftable between first and second positions in response to energization of said coil, and motion-translating means responsive to shifting movement of said pole piece into said second position to rotate said feed nut about said bearing means so as to shift said carriage in reverse direction, means for returning said motion-translating means to normal position when said coil is d-eenergized, and disengaging means responsive to the return movement of said motion-translating means for retracting said transducing head from said record.

iii. Apparatus as claimed in claim 9, wherein said motion-translating means comprises a magnetic member attracted into gripping engagement with said feed nut by energization of said coil and rotatable by the shifting movement of said pole piece, said disengaging means comprising means connected to said magnetic member.

ll. Sound reproducing apparatus comprising a carriage for effecting relative movement between a rotatable sound record and a transducing head, a feed screw for advancing the carriage, a rotatably mounted feed nut on said carriage and engaged with said feed screw, a first magnetic member rigidly attached to said feed nut and arranged for rotation therewith, a second magnetic mem ber positioned adjacent said first magnetic member, coil means adapted when energized to lock said two magnetic members together in gripping engagement, and operating eans actuated by the energization of said coil means to rotate said second magnetic member a predetermined small amount, thereby also rotating said first magnetic member and said feed nut to produce a backspacing step of said carriage, said operating means including means to hold said second magnetic member in position after said backspacing step to prevent further rotation of said first magnetic member so long as said coil means remains energized.

12. Sound reproducing apparatus comprising a carriage for effecting relative movement between a rotatable sound record and a transducing head, a feed screw for advancing the carriage, a rotatably mounted feed nut on said carriage and engaged with said feed screw, a disc-shaped magnetic member rigidly attached to said feed nut and coaxial therewith, a hollow cylindrical member of magnetic material mounted adjacent said disc-shaped member and coaxial therewith, said cylindrical member being supported for engagement between one end thereof and said disc-shaped member, coil means located within said sleeve member and effective when energized to attract said cylindrical member to said disc-shaped member to produce a gripping engagement therebetween at said one end of said cylindrical member, cam means operative with said cylindrical member to produce a small '3' rotational movement thereof, and operating meansresponsive to the energization of said coil means for actuating said cam means to produce a backspacing step of said carriage each time said coil means is energized.

13. Apparatus as claimed in claim 12, wherein said operating means comprises a second disc-shaped member of magnetic material at the other end of said cylindrical member and coaxial therewith, said second disc-shaped member being mounted for axial movement in response to the energization of said coil means, said cam means comprising elements on said second disc-shaped member engageable with corresponding angled surfaces of said cylindrical member.

'8 References Cited by the Examiner UNITED STATES PATENTS 2,690,529 9/54 Lindblad 317-192 2,873,412 2/59 Pratt 317-492 2,959,372 11/60 Sadorf 242158.2 X 2,961,243 11/60 Schueler 274-21 3,007,705 11/61 Matusche 274-21 FOREIGN PATENTS 659,975 5/38 Germany.

EVON C. BLUNK, Primary Examiner.

NORTON ANSHER, Examiner. 

2. FOR USE WITH A SOUND REPRODUCING MACHINE HAVING A CARRIAGE FOR EFFECTING ADVANCING MOVEMENT BETWEEN A ROTABLE SOUND RECORD AND A TRANSDUCING HEAD COOPERABLE WITH SAID RECORD, AND WHEREIN SAID CARRIAGE INCLUDES A NORMALLY STATIONARY FEED NUT ENGAGEABLE WITH A ROTATABLE FEED SCREW FOR PRODUCING THE ADVANCING MOVEMENT THEREOF; BACKSPACING APPARATUS COMPRISING BEARING MEANS FOR ACCOMODATING ROTAITONAL MOVEMENT OF SAID FEED NUT, ELECTROMAGNETIC MEANS INCLUDING A REMOTELY ENERGIZABLE COIL MOUNTED ON SAID CARRIAGE, ROTATING MEANS MOVABEL BY SAID COIL FROM AN INITIAL POSITION TO A SECOND POSITION SO AS TO ROTATE SAID FEED NUT AN INCREMENTAL STEP WHEN SAID COUL IS ENERGIZED, LOCKING MEANS ARRANGED TO MAGNETICALLY GRIP 